Do you have a water softener or use a lot of ph down/up. If it isn’t fungi, it could be salt build up. I get the salt build up on mine. I can’t see it well enough and and am not as experienced as lots here.
Just a thought.
Do you have a water softener or use a lot of ph down/up. If it isn’t fungi, it could be salt build up. I get the salt build up on mine. I can’t see it well enough and and am not as experienced as lots here.
Just a thought.